Hi shdcmj2,Just thought I'd clarify the difference between a cell and a box. The Puzzle grid contains 81 cells made up of nine "3X3" boxes. The top (upper) left box is box 1, the centre (middle) box is box 5 and the bottom (lower) right box is box 9.Cec

Oops! Thanks for pointing that out Ron. I can recall seeing "my" explanation posted in other threads but I now suspect additional notation mentioned that the boxes are numbered left to right to avoid the alternative layout that you have correctly pointed out. Fortunately, in this instance, shdcmj2 would still identify box1 as the top left corner box.

In hindsight, suggesting shdcmj2 should click on this LINK would have been better.